Surgical saw



June 10, 1941. s. L FlsHER A sURGIcAL sAw Filed June 11, 1938 3 Sheets-Sheet 1v ATTORNEY June 10, 1941. s. L. Pls-HER SURGICAL SAW `Filed June 11, 195s 3 Sheets-Sheet 2 @45% uA/7?; @ww

ATTO RN EY I IILIIIII mNW June 10, 1941. 2,244,683

s. L. FISHER SURGICAL SAW Filed June l1, 1938 3 Sheets-Sheet 3 ATTORNEY Patented June 10, 1941 UNITED STATES PATENT OFFICE SURGICAL SAW Samuel Lloyd Fisher, Brooklyn, N. Y.

Application June 11, 1938, Serial No. 213,115

10 Claims. (Cl. 128-317) This invention relates to surgical instruments in general and more especially to devices used in the medical profession in the treatment of bone fractures and the like.

Among the objects of the present invention, it is aimed to provide an improved portable combination motor and surgical instrument holder from which the .motor can be easiily removed to facilitate sterilization and the like.

1t is still another object of the present invention to provide an improved combination motor and tool holder suitable for receiving an attachment for operating a drill, Kirschner wire, saw or the like surgical instrument.

It is still another object of the present invention to provide an improved supporting guide for a Kirschner wire While being operated and the like.

It is also an object of the present invention to provide an improved combination shell and motor c which can be operatively connected with a high speed surgical drill, saw or the like or with a low speed router screw or the like Without interfering with any of the attributes essenltial to a surgical instrument that can be readily sterilized and satisfactorily retained in its sterilized condition.

These and other features, capabilities and advantages of the invention will appear from the subjoined detail description of one speciic embodiment thereof illustrated in the accompanying drawings in which Figure 1 is a longitudinal section of a combined motor and tool holder equipped with a rotary saw made according to the present invention;

Fig. 2 is a section on the line 2 2 of Fig. 1;

Fig. 3 is a section similar to the section of Fig. 2 but with one of the saws removed and a protecting cap attached in place;

Fig. 4 is a section on the line 4-4 of Fig. 3;

Fig. 5 is a rear elevation on a small scale of the motor containing shell illustrated in Fig. l;

Fig. 6 is a section on the line 6 6 of Fig. 1;

Fig. '7 is a diagrammatic view on the line '1 -I of Fig. 1;

Fig. 8 is a perspective of the operating switch detached from its associated parts;

Fig, 9 is a longitudinal section of an 4auxiliary shell with a reduction associated therewith and a screw holding attachment in operative associatien with the shell illustrated in Fig. 1;

Fig. 10 is an elevation showing two bone portions connected by a screw and the screw holder after having been removed from the screw;

Fig. ll is a Section on the line II-II of Fig. 10;

Fig. 12 is a section on the `line I2-I 2 of Fig. 9;

Fig. 13 is a section on the line I3-I3 of Fig. 12;

Fig. 14 is a longitudinal section of a Kirschner wire operating attachment connected to the shell shown in Fig. 1;

Fig. 15 is a section on the line I5-I5 of Fig. 14;

Fig. 16 is a section on the line IB-IB of Fig. 14.;

Fig. 17 is a. section on the line II-II oi Fig. 14;

Fig. 18 is a fragmental elevation of a portion of the main shell before a tool operating attachnient has been connected; and

Fig. 19 is a fragmental elevation of one ofthe guiding rods of the guide for the Kirschner wire illustrated in 14.

In Fig. l, there is shown a main shell I having attached thereto a handle 2. The shell I is provided to receive an electric motor 3 and equipped with a cover 4 positioned in place on the shell I by a bayonet slot connection 5.

The handle 2 in the present instance is equipped with an outlet plug 6 adapted to receive and stop shocks connected to a Source of current not shown. The plug 6 has connected thereto the conductors 1 and 8. The conductor 'I is connected in the present instance, see Fig. 8 to the contact 9 and the conducto-r 8 connected to the conducting bar I0. The contact 9 and bar Ill as shown areconnected to the support II having a second conducting bar I2. The conducting bar i2 has a conta-ct I3 at one end and a spring contact arm I4 at the other end. This contact arm I4 of the bar I2 and the spring contact arm I5 of the bar I0 exltend along one face of the shell I to engage the two contact buttons I6 and I 'I of the motor 3. The contact buttons I6 and I'I, see Fig. 6, are positioned in an insulating plate I8 adapted to engage the inner faces of the ribs 20 and 2I of the shell I, thereby to position the buttons I6 and I1 in contact connecting position with the spring arms I4 and I5.

As shown, the shell I is also preferably provided with the ribs 22 and 23 to cenfter the motor 3 relative to the shell I so that its shaft 24 and the pins 25 may be positioned to receive the slots of the intermediate connecting pieces hereinafter to be described.

The contacts 9 and I3 are normally open and adapted to be closed by engaging the contact points and 2l of the movable U-shaped Conductor 23 mounted on the trigger 25 pivotally connected to the handle 2 by the shaft 3S and normally positioned with the contacts Z6 and 2l spaced from the contacts and lil by the spring 3l.

The inotor 3 is preferably reversible having the four contacts 32, 33, 3d and 35, the contacts 32 and S3 as one pair and the contacts 36 and 3b as another pair in one case being connected to one another and the contacts 33 and 34 as one pair and the contacts 35 and 32 as another pair in another position for reversing the motor by means of the conducting plates 36 and 3l attached to the cover l and operable by the winged handle 33.

For high speed Working such as when a saw is to be operated or a Kirschner wire drill then preferably the extension 39 of the shell I has connected thereto an intermediate connecting device including a shell lill on which there is rotatably mounted the intermediate shaft element il having slots d'2 with cammed jaws to receive the pins 25 ofthe shaft 2li of the motor.

The intermediate shaft element has a similar set of slots 3 with similar cammed jaws. The intermediate shaft element M is further anchored to rotate in the shell Il@ by the screw it extending through the extension 3 and the shell di? and then into the annular slot d5 of the intermediate shaft element 4l.

From the foregoing, it will be seen that the intermediate shaft element 4| will normally rotate with the shaft 24 of the motor. On the other hand, when the motor is at rest and it is desired to anchor the intermediate shaft element il against rotation, the stop d is provided which extends through the extension 39 and shell ill ut is normally retained out of engagement with the intermediate shaft element M by the spring 41. Its inner end, however, is adapted to be pressed, into engagement with one of the slots 42 to anchor the saine against rotation when certain adjustments or assemblies are to be made hereinafter to be described.

The shell Ml, see particularly 18', is provided with cam Vslots d3 to receive suitable pins for connecting the shell to the tool to be operated. In the case of the saw illustrated in ligl 1, the cams 48 receive the pins 49 in the connecting ring 59 rotatably mounted on the cylindrical holder 5Ir through which extends the spin.- dle 52 o1 a shaft which. is connected by pins 53 which engage the slots i3 of the intermediate connecting member di the block 54 by the pin 55, which block 5d, see Fig; 2, consists of two cheek plates 5S and el forming an enlarged opening 5i! for the collar member 59 and having a narrow longitudinally extending cylindrical chamber extending therefrom to receive the outer portion 5E) of the spindle provided with a worm 5l in mesh with the Worin wheel 62 rotatably mounted in the chainber e3 at the outer end of the block 5F; formed by the plates 56 and 5l.

Through the worm wheel there extends a screw member having a diminished portion 5f# with an enlarged right hand threaded portion G5 to one side and an enlarged left hand threaded portion @g5 on the other side. portion is integral with the diminished portion Sii and the portion t6 is secured to the diminished portion ed. The portion 5 is rotatably mountedV in the worin wheel B?. Preferably as shown, the exposed end of the threaded portion The shell 5l is iiXed to In the present instance, the

iii)

65 is provided with a lieyway for the reception of a key whereby the threaded portions @5 and may be rotated at any time. The threaded portions @5 and 6 are provided to receive and position the rotary saws l and t8 when two saws are used or to position a single saw, as for instance the saw 6l see Fig. 3 and a protection cap 6d. The saws Si and $8 when -both are used are conformed to be mounted as a set, the saw 6l having a hub 7G secured thereto and the hub lil provided with a pin i,'a pin receiving orifice l2 and an internally threaded opening 'i3 to receive the threaded portion and the saw $8 is provided with a similar hub lli, the hub 'id having a pin 15, a pin receiving opening "l5, and an internally threaded chamber 'il to receive the threaded portion iid. rihe worin wheel 52 is provided with two pin receiving openings i3 and i9, the opening it alining with the opening l2 of the hub 'iii and with the pin 'iii to receive the same as shown in Fig. 2 when the openings i9, 'It will be in alinement to receive the pin li.

By means of the key to be inserted in the keyway El, it will thus beV seen that the screw member containing the threaded portions 55 and i may be turned either to mount the saws El and 58 close to one another as shown in Fig. 2 or at any number of desired distances apart depending upon the length'of the combined hubs H3 and 14 and the intermediate portion 32 of the worm wheel 622.V Y

It will be noted that the ring E@ preferably has three projections S3 as particularly shown in Fig. l'l by the projections 8d, 85 and 8% o the locking ring 8l there shown to facilitate rotating the ring 5i? especially when the operator-s hands are covered by surgeons gloves and wet.

When a single saw is to be used, as an instance, the saw El, see particularly Fig. 3, it is preferable to provide a protecting cap, such as the cap Se illustrated in Fig. 3 to prevent the admission of any gauze or other material used in the operation. For this purpose the cap $9 is substantially identical to the hub ifi of the saw 68 with the exception that it is not equipped with a saw.

In Fig. 14, the slots d3 of the intermediate portion lil receive the pins 38 of the spindle 89 which is rotatably mounted in the chanibered block QS. For securing the chainbered block to the extension 4Q a pin .fil is provided in the ring 2l. By manipulation of the projections Sil, 85 and da', the pin Sl may be moved over into the innermost position of the cam slot t8 for anchoring the block t to the extension liti.

Preferably as shown, when the spindle Se is intended directly to engage the tool to be manipulated, there will `be provided integral with the spindle S9 a chainbered extension S2 having an external screw thread Q3 to receive the clamping nut 17?. The extension 92 is conformed to receive in the present instance three jaw elements 55 having cam faces de to cooperate with the inner cam faces of the clamping nut t. and to receive between the three jaws 55 the drilling rod 9'! or other drilling tool. in the present instance is shown as typical of the well known Kirschner bone drilling wire.

.Since the length of the Kirschner wire Sl is not infrequently very considerable, in order to support the same while it is being rotated in the act of drilling, the supporting device now to be described is provided.

This supporting device consists essentially of three equally spaced cylindrical elements 98, 99

and ld formed on the block l which are The drilling rod p adapted to receive the outermost telescoping cylinders three in number secured to the bracket |02, which telescoping elements |0| in turn are adapted to receive the three telescoping elements |03 secured to the bracket |04 which in turn are adapted to receive the three telescoping elements |05 secured to the brackets |06 and |31. The brackets |02, |04, |06 and |01 are in addition provided with a central orifice to receive the drilling wire 91, see for instance the orifice |08 in the bracket |06.

In order to frictionally anchor the guiding rods |05 in the guiding elements |03 and in turn the guiding elements |03 in the guiding elements |0| preferably, see Fig. 19, slots are formed as an instance the slots |09 and |50 with intervening tongue I depressed resiliently to engage a rod element |05 and similarly the elements |0| provided with slots ||2 and ||3 with an intervening tongue ||4 depressed resiliently to engage a guiding element |33.

The present invention also aims to reduce the parts in a surgeons kit to a minimum and for this reason shows a reducing element which may be attached to the shell for operating, as an instance, a slow turning binding screw for binding two bone elements such as the elements ||5 and ||6 to one another. In the present instance, there is shown as attached to the reducing element the screw |11 which has a tapered end ||8 and an angular head i9 to be gripped by a tool holder having a spring finger |2| frictionally to engage one side of the angular h ead H9. The tool holder |20 has a spindle 22 which may be connected to the driven shaft |23 by any suitable means, such for instance as the intermediate element 223 having recesses to receive pins on the shaft |23, such as the pins on the shaft 24 and the locking nut |24 provided to secure locking jaws to the spindle |22 such as the locking jaws 95, in which case the intermediate element 223 is journaled in the bearing |25 supported by the end wall |26 of the auxiliary shell |21., while the shaft |23 is preferably journaled as shown in the partitions u |28 and |29.

On the shaft |23, there is fixed in the present instance, the gear |30 in mesh with the small gear |3| on the shaft |32, which shaft |32 is journaled in the partitions |28 and |29. On the l shaft |32, there is fixed the large gear |33 in mesh with the small gear |34 on the shaft |35 also journaled in the partitions |28 and |29. On the shaft |35, there is fixed the large gear |33 in mesh with the small gear |31 xed on the shaft |38 also journaled in the partitions |28 and |29.

On a portion of the shaft |33 extending between the partition |28 and the end wall |26, there is fixed the large gear |39 in mesh with the small gear |40 fixed on the shaft |4I journaled in the block |42 and the partition |23. The inner end of the shaft |4| is provided with pins |43 to receive the slots |44 of the intermediate connecting member |45 provided with slots |46 to receive the pins Z5 on the shaft 24 of the motor 3.

The shell |21 is provided with a bayonet slot |41 to receive the pin |48 on the shell i and thus lock it in position.

The handle or grip 2, as particularly shown in Fig. 1 is preferably positioned well beneath the center of gravity of the instrument to facilitate balancing the same so necessary in the easy operation of the instrument.

Preferably also, see the direction of the teeth |50 of the saw 62 in Fig. 1,-when rotating in the direction of the arrow |5I, the saw will tend to throw the bone dust or other anatomical matter out of the field of vision of the operator. The saw attachment shown in Fig. 1 is of course intended mainly for bone grafting operations where the incision in the flesh to accommodate the saw may be reduced to a minimum and merely suicient to receive the saw, either a single blade or double blade as the case may be. In other words, with this attachment, it will not be necessary -to extend the width of the incision to provide space for manipulating the instrument as is the case withthe ordinary instruments heretofore used.

It will also be apparent with this instrument that when the two blades are used and after two parallel cuts have been made in a bone, that one of the blades can be quickly removed as an instance the blade 63 and the cap 39 thereupon secured in place and then the ends of sections of bone so dened cut by the single blade and the section or sections quickly slid along the groove so formed in a minimum period of time.

Furthermore, it will alsoI appear that if the operator should then wish entirely to remove.

the saw attachment and replace it with another attachment, the projections 83 will facilitate loosening the saw attachment andrsecuring another attachment in place thereof, the projections accommodating themselves readily to the slippery gloved fingers of the attendant or operator so that the removal and ysubstitution can take place in the shortest interval of time possible.

Positively to prevent the saw from turning with the shaft 52, the abutting ends of the shells 5| and 40 are provided with cooperating projections and notches |52, preferably four in number.

The screw ||1 is formed to facilitate movement of the same in a predetermined straight line. As an instance,the end ||8 is provided with a centrally located point |53 from which the screw tapers outwardly into the tapered portion ||8 to the main body portion with a very gradual incline to the thread approximating forty-five degrees to the axis of the screw. This screw ||1 as shown in Fig. 10 is intended to be left in the bone until the fractured pieces have knit and in some cases is left there permanently.

In View of the foregoing, after the drill attachment shown in Fig. 9 has turned the screw ||1 into place, the spring lip |2| comes into play, it then only being necessary to frictionally slip the spindle |22 from the screw head ||9 and leave the screw ||1 in the bone. In some cases, it may be desirable to remove the screw Hl' after the bone portions have become knit. Then it will only be necessary to make a small incision to expose the head ||9 and then frictonally slip the spindle |22 into place, set the motor for reverse movement by turning the wing elements 39 to register with they mark L and then press the trigger 29 in the regular Way and the screw will be rotated in the reverse direction and removed.

The reduction unit used when a screw, such as the screw ||1 is to be secured in place or removed has already been explained, the reduction in revolutions per minute being approximately from sixteen thousand R. P. M. to one hundred R. P. M. which is reduced to eighty R. P. M. under load whereby any boring or drilling action will be effectively avoided and the screw merely cut itself into a locking position in the bone. Obviously since the screw IiI is intended to be left in the bone tissue, it is desirable to produce these screws from non-oxidizing metal, such as stainless steel or the like.

When the wire drill is used, it is particularly desirous to have the wire Sl drill through a bone in a perfectly straight path since experience has taught that in such cases the accompanying pain to the patient when traction is made may be reduced to a minimum if not entirely eliminated. With the present guiding elements I|l|, |93 and |95 and the combination motor holder and instrument attachment, the operating surgeon is merely called upon to hold the motor steady after making contact. After the wire Si has so been drilled through the bone, the ordinary Kirschner horse-shoe clamp may be used to maintain the wire stretched in a straight line and then the weight attached to the horseshoe clamp in the usual way.

Before the horseshoe clamp aforesaid is attached in order to remove a wire 97 from the drilling attachment in some instances, the same is cut o leaving a small portion in the drilling attachment. In other cases, the guiding elements lill, |03 and |65 are moved away from the shell to clear the ring 8'! whereupon the projections 84, 35Y and 85 are engaged and turned. To prevent the wire 91 fromturning during this procedure, the motor 3 is rst shut off and then the stop pin I5 engaged and pressed to enter one of the slots 42 whereupon the ring 85 can with facility be turned, and thereupon the guiding elements IBI, m3, |95 and wire drill attachment removed whereupon the clamping nut dit can be turned to release the jaws 95 or else the nut 9d turned to release the jaws 95 before the ring 8l is turned.

Preferably the motor 3 has a cylindrical housing |54 having a diminished cylindrical portion |55 conformed to t snugly in the ring IE having an annular flange secured to the inner end of the shell I concentric with the opening formed by the diminished projection 39. When the motor 3 is positioned with its diminished end |55 locked in the ring |55, the motor 3 is resiliently locked in such position by the cover 4 due to the spring fingers |51 formed thereon and engaging the rear end |58 ofthe motor 3, see Figs. 1, 6 and '7.

It is obvious that various changes and modiications may be made to the details of construction without departing from the general spirit of the invention as set forth in the appended claims.

I claim:

l. In a surgical instrument, the combination of a main shell having a cylindrical projection for receiving an electric motor with its shaft protruding into said projection, a block, means for removably connecting said block to said projection, a second shaft in said block and operatively associated with the motor shaft, a worm on said second shaft, a bearing at the outer end .of said block, worin wheel shaft elements journaled in said bearing, a worm wheel iixed to said worm wheel shaft elements and in mesh with said worm, hubs on said worm wheel shaft elements, yand a pair of rotary saws removably connected to the opposite ends of said hubs for sole or joint use.

2. In a surgical instrument, the combination of a main shell having a cylindrical projection for receiving an electric motor with its shaft protruding into said projection, a block, means for removably connecting said block to said projection, a second shaft in said block and operatively associated with the motor shaft, a worm on said second shaft, a bearing at the outer end of said block, Worm wheel shaft elements journaled in said bearing, a worm wheel associated with said worm wheel shaft elements and in mesh with said worm, hubs on said worm wheel shaft elements, a pair of rotary saws removably connected to said hubs on opposite sides of said worm wheel, and means for adjusting the spacing of said saws relative to one another.

3. In a surgical instrument, the combination of a main shell having a cylindrical projection for receiving an electric motor with its shaft protruding into said projection, Va bearing removably connected to said projection, a second shaft in said bearing, an intermediate connecting shaft element in said bearing operatively associating said second shaft with the motor shaft, a split block secured to the end of said bearing and hav- .ing a chamber, a worm on the end of said second shaft, a worm wheel shaft journaled in said chamber, a worm wheel mounted on said worm wheel shaft and in mesh with said worm, a rotary saw having an internal screw threaded hub and an axially extending pin, there being a pin opening in said worm wheelA to receive said pin, and a stem extending through said worm wheel and having a screw threaded portion thereon to receive the screw threaded portion of said hub.

4. In a surgical instrument, the combination of a main shell having a cylindrical projection for receiving an electric motor with its shaft protruding into said projection, a bearing removably connected to said projection, a second shaft in said bearing, an intermediate connecting shaft element in said bearing operatively associating said second shaft with the motor shaft, a split block secured to the end of said bearing and having a chamber, a worm on the end of said second shaft, a worm wheel shaft journaled in said chamber, a worm wheel on said worm wheel shaft and in mesh with said worm, a pair of rotary saws having internally screw threaded hubs and axially extending pins and pin openings, there being pin openings in said worm wheel to receive said pins, a stem extending through said worm wheel and having a right hand screw threaded portion on one end and a left hand screw threaded portion on the other end to receive the screw threaded portions of said hubs and thereby facilitate spacing the saws from one another the required distance, and a key receiving opening in an end of said stem to facilitate turning said stem.

5. In a surgical instrument, the combination of a main shell having a cylindrical projection for receiving an electric motor with its shaft protruding into said projection', a bearing removably connected to said projection, a second shaft in said bearing, an intermediate connecting shaft element in said bearing operatively associating said second shaft with the motor shaft, a split block securedl to the end of said bearingr and having a chamber, a worm on the end of said second shaft, a worm wheel shaft journaled in said chamber, a worm wheel mounted on said worm wheel shaft and in mesh with said worm, a rotary saw and a cap having internally screw threaded hubs and axially extending pins and pin openings to receive the pins of one another,

there being pin openings in said worm wheel to receive said pins, and a stem extending through said worm Wheel and having a right hand screw threaded portion on one end and a left hand screw threaded portion on the other end to receive the screw threaded portions of said hubs and thereby facilitate securing both saw and cap in position.

6. In a surgical instrument, the combination of a bearing, a motor-driven shaft mounted in said bearing, a worm on said shaft, a worm wheel shaft journaled in the outer end of said bearing, a worm wheel mounted on said worm wheel shaft and in mesh with said worm, a. pair of rotary saws removably connected to said worm wheel on opposite sides of said worm wheel, and means for adjusting the spacing of said saws relative to one another.

7. In a surgical instrument, the combination of a bearing, a motor-driven shaft journaled in said bearing, a split block secured to the end of said bearing and having a chamber, a worm on the end of said shaft, a worm wheel shaft journaled in said chamber, a worm wheel on said worm wheel shaft and in mesh with said worm, a rotary saw having an internal screw threaded hub and an axially extending pin, there being a pin opening in said worm wheel to receive said pin, and a stem extending through said worm wheel and having a screw threaded portion thereon to receive the screw threaded portion of said hub.

8. In a surgical instrument, the combination of a bearing, a motor-driven shaft mounted in sai-d bearing, a split block secured to the end of said bearing and having a chamber, a worm on the end of said shaft, a worm Wheel shaft journaled in said chamber, a worm wheel mounted on said worm wheel shaft and in mesh with said worm, a pair of rotary saws having internally screw threaded hubs and axially extending pins and pin openings, there being pin openings in said worm wheel to receive said pins, a stem extending through said worm Wheel and having a right-hand screw threaded portion on one end and a left-hand screw threaded portion on the other end to receive the screw threaded portions of said hubs and thereby facilitate spacing the saws from one another the required distance, and a key receiving opening in an end of said stem to facilitate turning said stem.

9. In a surgical instrument, the combination of a bearing, a motor-driven shaft journaled in said bearing, a split block secured to the end of said bearing and having a chamber, a worm on the end of said shaft, a worm wheel shaft journaled in said chamber, a worm Wheel mounted on said worm wheel shaft and in mesh with said worm, a rotary saw and a cap having internally screw threaded hubs and axially extending pins and pin openings to receive the pins of one another, there being pin openings in said Worm wheel to receive said pins, and a stem extending through said Worm wheel and having a righthand screw threaded portion on one end and a left-hand screw threaded portion on the other end to receive the screw threaded portions of said hubs and thereby facilitate securing both saw and cap in position.

10. In a surgical instrument, the combination of a shell, a motor-driven shaft mounted in said shell, a. worm on said shaft, a bearing at the outer end of said shell, worm wheel shaft elements journaled in said bearing, a worm Wheel associated with said worm wheel shaft elements and in mesh with said worm, hubs on said worm wheel shaft elements, and a pair of rotary saws removably connected to said hubs on opposite sides of said worm wheel .for sole or joint use.

SAMUEL LLOYD FISHER. 

